Effect of internal flow of Venturi-type power generation device on piston movement

Abstract

ABSTRACT In the development and utilisation of hydraulic resources, high head and low flow hydraulic resources have not been fully utilised. To develop hydronic resources with low flow at high heads, this work designs a Venturi-type power generation device and studies the internal flow of the device by combining experiments and numerical simulations. The results indicate that the diameter ratio of the leading and branch pipes in the device significantly impacts pressure loss, and the diameter ratio at the throat is close, resulting in a significant pressure loss and an impact on the internal flow of the primary pipe. When the flow rate ratio of the leading and branch pipes is more than 4.03%, the piston can complete the reciprocating stroke, and the completion time decreases with the flow rate increase. When the flow rate ratio of the primary and branch pipes reaches 5.27%, the completion time approaches its limit. When the flow rate of the Venturi primary pipe is greater than 30 m3/h, the device begins to experience local cavitation, and noticeable noise appears at the diffusion tube.